無摩擦流動 的英文怎麼說
中文拼音 [wúmócāliúdòng]
無摩擦流動
英文
frictionless flow- 無 : 無Ⅰ動詞(沒有) not have; there is not; be without Ⅱ名詞1 (沒有) nothing; nil 2 (姓氏) a surn...
- 摩 : 摩構詞成分。
- 擦 : 動詞1 (摩擦) rub 2 (用布、 手巾等摩擦使干凈; 揩拭; 抹) wipe; scrub; clean 3 (塗抹; 搽) spre...
- 流 : Ⅰ動1 (液體移動; 流動) flow 2 (移動不定) drift; move; wander 3 (流傳; 傳播) spread 4 (向壞...
- 摩擦 : 1 (互相接觸的兩物體作來回相對運動) rub; chafe 2 [物理學] (相互接觸的兩物體在接觸面上發生阻礙相...
- 流動 : 1. (液體或氣體移動) flow; run; circulate 2. (經常變換位置) going from place to place; on the move; mobile
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Based on the review, the fluid flow and heat transfer in the curved circular and rectangular pipes have been researched by employing perturbation method and numerical simulation with a physical model under the rotational orthogonal curvilinear coordinate in a rotating curvilinear pipe with multi - parameters. we firstly analyzed the fully developed fluid flow and heat transfer, mixed convection heat transfer, the development of flow and heat transfer in the inlet in different cross section ( circular, elliptical, annular and rectangular crossection ). the variations of the secondary flow, axial velocity, distribution of temperature, the friction force on the wall, the ratio of friction factor as well as the nusselt number with different dimensionless parameters had been examined in detailed
本文在總結和分析了一個世紀以來有關曲線管道流動和換熱特性的研究成果的基礎上,以旋轉正交曲線坐標系統下的多參數旋轉螺旋管道中的對流傳熱為物理模型,通過攝動方法和有限體積法,首次對各種截面(圓截面、橢圓截面、環形截面、矩形截面)旋轉曲線管道內充分發展流動的流動結構和傳熱特性(包括耦合對流傳熱特性)以及旋轉曲線管道開口段發展流動的流動結構和換熱特性進行了系統的數值模擬和理論分析,詳細討論了各種無量綱參數對管道內軸向速度分佈、二次流結構、溫度分佈、壁面摩擦力、摩擦系數比以及管道nusselt數的影響,獲得了若干創新性成果。A method is provided to measure the friction parameters of the bed. the maximum friction torque, coulomb friction torque, viscous friction coefficient and moment of inertia can be gotten by fitting the free reduced rate curve of the gimbals and measuring the motor current when the motor begins to rotate
提出了一種測量轉臺摩擦特性的方法,通過對轉臺在無外推力作用下的速度衰減曲線的擬合以及電機啟動過程電流和轉速的測量,可以得到最大靜摩擦力矩、庫侖摩擦力矩、粘滯摩擦系數及轉動慣量。Against two kinds of nonlinear friction observers, the analytic expression of zero ve - locity interval t based on the nonlinear model of brushless dc motor system is deduced in this paper. simulation results indicate that the system performance at low velocity can be im - proved effectively using the friction observer based on coulomb friction model
針對兩種不同的非線性摩擦觀測器,推導了基於無刷直流電動機非線性模型的零速度時間間隔腡解析表達式,通過模擬證實,利用基於庫侖摩擦模型的摩擦觀測器可以有效地改善系統的低速控制性能。Compensation of friction in brushless dc motor system
無刷直流電動機系統的一種摩擦補償方法研究Presents a simple method of compensating friction against the character of the nonlinear model of a brushless dc motor system which transfers the original system model to a simple linear model using the method of input - output linearization, and estimates the coulomb friction in the system in real - time using a nonlinear friction estimator, and then compensate the friction in the system using a friction feedforward, and concludes from simulation results that this method can effectively eliminate the influence of friction in brushless dc motor systems
針對無刷直流電動機系統的非線性數學模型特點,提出了一種簡單的摩擦補償方法.該方法首先利用輸入輸出線性化方法將原系統模型轉化為一種簡單的線性模型,然後給出一種非線性摩擦估計器實時估計系統中的庫侖摩擦值,最後利用摩擦前饋補償方法對其進行補償.模擬結果表明該方法可以有效地抑制無刷直流電動機系統中的摩擦影響However, the traditional dc motor uses brush so as to switch the phases, so there are relative mechanical frictions. then it comes out many fatal failing, such as yawp, spark, wireless disturb, etc. what " s more, its making cost is high, its maintain is also difficult, therefore its application is greatly limited
直流電動機具有運行效率高和調速性能好等諸多優點,但傳統的直流電動機均採用電刷,以機械方法換向,因而存在相對的機械摩擦,由此帶來了噪聲、火花、無線電干擾以及壽命短等致命弱點,再加上製造成本高及維修困難等缺點,從而大大地限制了它的應用范圍。分享友人